# 2024 McDonald criteria for multiple sclerosis McDonald 2024 Status: LIVE Price: $0.005 USDC `GET /api/calc/mcdonald_2024` HTML: https://magentlab.com/docs/mcdonald-2024 Markdown: https://magentlab.com/docs/mcdonald-2024.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Apply Montalban 2025 / 2024 McDonald criteria for typical clinically isolated syndrome and return whether mcdonald_ms holds from caller-assigned typical CIS, no better explanation, attacks, lesions, five DIS topographies (including optic nerve), MRI DIT, CSF-specific oligoclonal bands, and CSF kappa free-light chains. ## When to use When an agent already has typical CIS versus not, whether a better explanation exists, ≥2-attack and ≥2-lesion flags, five caller-assigned 2024 DIS topographies, MRI DIT, CSF-specific OCB, and a kappa FLC flag, and needs the published relapsing/CIS combination. magent does not read MRI, OCT, or VEP and does not assay CSF. ## When not to use - Not a medical device and not a diagnosis of multiple sclerosis. - Relapsing / typical CIS pathway only. Does not implement 2024 primary progressive MS (PPMS) or radiologically isolated syndrome (RIS). - Not the 2017 McDonald criteria (Thompson 2018). 2024 adds optic nerve as a fifth DIS location and treats kappa free-light chains as interchangeable with oligoclonal bands. - Does not apply age ≥50 extra specificity requirements, central vein sign, paramagnetic rim lesions, or a 4-of-5 DIT-waive shortcut. - magent does not read MRI, OCT, or VEP and does not assay CSF. The five topographies, MRI DIT, CSF-specific OCB, and csf_kflc are caller-assigned. csf_kflc is a positive/negative flag, not a numeric kFLC index cutoff. - Remain vigilant for NMOSD and other better explanations; no_better_explanation is caller-assigned. ## Formula ``` mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis ``` ## Citation [Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria](https://doi.org/10.1016/S1474-4422(25)00270-4) Montalban X, Lebrun-Frénay C, Oh J, et al. Lancet Neurol. 2025;24(10):850-865 DOI: [10.1016/S1474-4422(25)00270-4](https://doi.org/10.1016/S1474-4422(25)00270-4) ## Worked example ### Two attacks and two lesions meet 2024 McDonald without DIS or CSF Given: `cortical_or_juxtacortical=false, csf_kflc=false, csf_specific_ocb=false, dit_mri=false, infratentorial=false, no_better_explanation=true, optic_nerve=false, periventricular=false, spinal_cord=false, two_or_more_attacks=true, two_or_more_lesions=true, typical_cis=true` 1. typical_cis true and no_better_explanation true 2. two_or_more_attacks true and two_or_more_lesions true (row 1) 3. five topographies, MRI DIT, OCB, and kappa FLC are not required on this row 4. dis false; mcdonald_ms true ### CIS with two of five topographies and kappa FLC (2024 DIT substitute) Given: `cortical_or_juxtacortical=false, csf_kflc=true, csf_specific_ocb=false, dit_mri=false, infratentorial=false, no_better_explanation=true, optic_nerve=true, periventricular=true, spinal_cord=false, two_or_more_attacks=false, two_or_more_lesions=false, typical_cis=true` 1. first/CIS attack and one lesion 2. periventricular true and optic_nerve true (DIS = ≥2 of 5) 3. dit_mri false, csf_specific_ocb false, csf_kflc true 4. 2024: kappa FLC may substitute for DIT when DIS is met 5. dis true; mcdonald_ms true ### CIS with one lesion and fewer than two topographies is not MS Given: `cortical_or_juxtacortical=false, csf_kflc=false, csf_specific_ocb=false, dit_mri=false, infratentorial=false, no_better_explanation=true, optic_nerve=false, periventricular=false, spinal_cord=false, two_or_more_attacks=false, two_or_more_lesions=false, typical_cis=true` 1. typical_cis true and no_better_explanation true 2. first/CIS attack, one lesion, all five topographies false 3. row 4 needs DIS plus DIT, OCB, or kappa FLC 4. dis false; mcdonald_ms false ## Also searched as - McDonald criteria 2024 - 2024 McDonald MS diagnosis - Montalban 2025 McDonald - CIS dissemination in space optic nerve - kappa free light chains MS - McDonald DIS five topographies - 2024 revisions McDonald criteria - clinically isolated syndrome 2024 ## Parameters - `typical_cis` (boolean, required): Typical clinically isolated syndrome as assigned by the caller (Montalban 2025 typical CIS / relapsing pathway). If false, mcdonald_ms is false; this tool does not diagnose MS from atypical presentations, PPMS, or RIS. true or false. magent does not examine the patient. - `no_better_explanation` (boolean, required): No better explanation for the presentation as assigned by the caller (Montalban 2025). If false, mcdonald_ms is false. Remain vigilant for NMOSD. true or false. magent does not assign a better explanation. - `two_or_more_attacks` (boolean, required): ≥2 clinical attacks as assigned by the caller. true means two or more attacks; false means this is the first/CIS attack. true or false. magent does not date attacks. - `two_or_more_lesions` (boolean, required): Objective clinical evidence of ≥2 lesions as assigned by the caller. true means ≥2 lesions; false means 1 lesion. true or false. magent does not examine the patient. - `periventricular` (boolean, required): Caller-assigned typical periventricular MS lesion topography (one of five 2024 DIS locations). true or false. magent does not read MRI. - `cortical_or_juxtacortical` (boolean, required): Caller-assigned typical cortical or juxtacortical MS lesion topography (one of five 2024 DIS locations). true or false. magent does not read MRI. - `infratentorial` (boolean, required): Caller-assigned typical infratentorial MS lesion topography (one of five 2024 DIS locations). true or false. magent does not read MRI. - `spinal_cord` (boolean, required): Caller-assigned typical spinal-cord MS lesion topography (one of five 2024 DIS locations). true or false. magent does not read MRI. - `optic_nerve` (boolean, required): Caller-assigned typical optic-nerve topography (fifth 2024 DIS location; Montalban 2025). true or false. magent does not read MRI, OCT, or VEP. - `dit_mri` (boolean, required): MRI dissemination in time as assigned by the caller (simultaneous Gd-enhancing and non-enhancing lesions, or a new T2 or Gd-enhancing lesion on follow-up vs baseline). true or false. magent does not read MRI. - `csf_specific_ocb` (boolean, required): CSF-specific oligoclonal bands as assigned by the caller (2024 DIT substitute; interchangeable with kappa free-light chains). true or false. magent does not assay CSF. - `csf_kflc` (boolean, required): CSF kappa free-light chains positive as assigned by the caller (2024: interchangeable with oligoclonal bands as the CSF DIT marker). Caller-assigned flag only; this tool does not apply a numeric kFLC index cutoff. true or false. magent does not assay CSF. ## Bulk (POST) POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement. Method: `POST /api/calc/mcdonald_2024` Max items: 25 Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic) Status: PREVIEW - 1 to 25 items. Each item uses the same keys as the GET query parameters. - POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows. - The first invalid item fails the whole request (index in the 400 JSON). You are not charged. - HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row. - Catalog misses (empty matches, found=false) stay paid 200s inside that slot. - x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items. Example request: ```json { "items": [ { "cortical_or_juxtacortical": "false", "csf_kflc": "false", "csf_specific_ocb": "false", "dit_mri": "false", "infratentorial": "false", "no_better_explanation": "true", "optic_nerve": "false", "periventricular": "false", "spinal_cord": "false", "two_or_more_attacks": "true", "two_or_more_lesions": "true", "typical_cis": "true" }, { "cortical_or_juxtacortical": "false", "csf_kflc": "false", "csf_specific_ocb": "false", "dit_mri": "false", "infratentorial": "false", "no_better_explanation": "true", "optic_nerve": "false", "periventricular": "false", "spinal_cord": "false", "two_or_more_attacks": "true", "two_or_more_lesions": "true", "typical_cis": "true" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/mcdonald-2024 Example 200: ```json { "count": 2, "path": "/api/calc/mcdonald_2024", "items": [ { "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.", "doi": "10.1016/S1474-4422(25)00270-4", "id": "montalban-2025", "pmid": "40975101", "source": "Lancet Neurol. 2025;24(10):850-865", "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria" }, "formula": "mcdonald_2024", "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis", "criteria": [ { "factor": "typical_cis", "met": true }, { "factor": "no_better_explanation", "met": true }, { "factor": "two_or_more_attacks", "met": true }, { "factor": "two_or_more_lesions", "met": true }, { "factor": "periventricular", "met": false }, { "factor": "cortical_or_juxtacortical", "met": false }, { "factor": "infratentorial", "met": false }, { "factor": "spinal_cord", "met": false }, { "factor": "optic_nerve", "met": false }, { "factor": "dis", "met": false }, { "factor": "dit_mri", "met": false }, { "factor": "csf_specific_ocb", "met": false }, { "factor": "csf_kflc", "met": false }, { "factor": "relapsing_cis_pathway", "met": true }, { "factor": "mcdonald_ms", "met": true } ], "cortical_or_juxtacortical": false, "csf_kflc": false, "csf_specific_ocb": false, "dis": false, "dit_mri": false, "infratentorial": false, "mcdonald_ms": true, "no_better_explanation": true, "optic_nerve": false, "periventricular": false, "spinal_cord": false, "two_or_more_attacks": true, "two_or_more_lesions": true, "typical_cis": true }, { "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.", "doi": "10.1016/S1474-4422(25)00270-4", "id": "montalban-2025", "pmid": "40975101", "source": "Lancet Neurol. 2025;24(10):850-865", "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria" }, "formula": "mcdonald_2024", "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis", "criteria": [ { "factor": "typical_cis", "met": true }, { "factor": "no_better_explanation", "met": true }, { "factor": "two_or_more_attacks", "met": true }, { "factor": "two_or_more_lesions", "met": true }, { "factor": "periventricular", "met": false }, { "factor": "cortical_or_juxtacortical", "met": false }, { "factor": "infratentorial", "met": false }, { "factor": "spinal_cord", "met": false }, { "factor": "optic_nerve", "met": false }, { "factor": "dis", "met": false }, { "factor": "dit_mri", "met": false }, { "factor": "csf_specific_ocb", "met": false }, { "factor": "csf_kflc", "met": false }, { "factor": "relapsing_cis_pathway", "met": true }, { "factor": "mcdonald_ms", "met": true } ], "cortical_or_juxtacortical": false, "csf_kflc": false, "csf_specific_ocb": false, "dis": false, "dit_mri": false, "infratentorial": false, "mcdonald_ms": true, "no_better_explanation": true, "optic_nerve": false, "periventricular": false, "spinal_cord": false, "two_or_more_attacks": true, "two_or_more_lesions": true, "typical_cis": true } ] } ``` ## Response fields - `formula` (string): mcdonald_2024 - `formula_expression` (string): Montalban 2025 / 2024 McDonald typical CIS combination - `mcdonald_ms` (boolean): true iff typical_cis, no_better_explanation, and a published relapsing/CIS row hold. Not a diagnosis. Not PPMS. Not RIS. Not 2017 McDonald. - `typical_cis` (boolean): Caller-assigned typical clinically isolated syndrome flag used - `no_better_explanation` (boolean): Caller-assigned no-better-explanation flag used - `two_or_more_attacks` (boolean): Caller-assigned ≥2 clinical attacks flag used - `two_or_more_lesions` (boolean): Caller-assigned objective clinical evidence of ≥2 lesions flag used - `periventricular` (boolean): Caller-assigned periventricular topography flag used - `cortical_or_juxtacortical` (boolean): Caller-assigned cortical or juxtacortical topography flag used - `infratentorial` (boolean): Caller-assigned infratentorial topography flag used - `spinal_cord` (boolean): Caller-assigned spinal-cord topography flag used - `optic_nerve` (boolean): Caller-assigned optic-nerve topography flag used (fifth 2024 DIS location) - `dis` (boolean): Computed 2024 dissemination in space: true iff at least two of the five caller-assigned topographies are true - `dit_mri` (boolean): Caller-assigned MRI dissemination in time flag used - `csf_specific_ocb` (boolean): Caller-assigned CSF-specific oligoclonal bands flag used - `csf_kflc` (boolean): Caller-assigned CSF kappa free-light chains flag used (interchangeable with OCB; not a numeric cutoff) - `criteria` (array): Rows for each caller flag, computed dis, relapsing_cis_pathway, and mcdonald_ms with factor and met - `citation` (object): Montalban 2025 Lancet Neurol McDonald citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.", "doi": "10.1016/S1474-4422(25)00270-4", "id": "montalban-2025", "pmid": "40975101", "source": "Lancet Neurol. 2025;24(10):850-865", "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria" }, "formula": "mcdonald_2024", "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis", "criteria": [ { "factor": "typical_cis", "met": true }, { "factor": "no_better_explanation", "met": true }, { "factor": "two_or_more_attacks", "met": true }, { "factor": "two_or_more_lesions", "met": true }, { "factor": "periventricular", "met": false }, { "factor": "cortical_or_juxtacortical", "met": false }, { "factor": "infratentorial", "met": false }, { "factor": "spinal_cord", "met": false }, { "factor": "optic_nerve", "met": false }, { "factor": "dis", "met": false }, { "factor": "dit_mri", "met": false }, { "factor": "csf_specific_ocb", "met": false }, { "factor": "csf_kflc", "met": false }, { "factor": "relapsing_cis_pathway", "met": true }, { "factor": "mcdonald_ms", "met": true } ], "cortical_or_juxtacortical": false, "csf_kflc": false, "csf_specific_ocb": false, "dis": false, "dit_mri": false, "infratentorial": false, "mcdonald_ms": true, "no_better_explanation": true, "optic_nerve": false, "periventricular": false, "spinal_cord": false, "two_or_more_attacks": true, "two_or_more_lesions": true, "typical_cis": true } ``` ## Errors - HTTP 400 `invalid_mcdonald_2024`: 2024 McDonald typical-CIS flags must each be true or false as used in the Montalban 2025 relapsing typical-CIS pathway. Returned before settlement; you are not charged. - HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged. - HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged. - HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged. Shared HTTP 402 and 503: https://magentlab.com/docs/payments ## Related tools - [McDonald 2017](https://magentlab.com/docs/mcdonald-2017) — Apply Thompson 2018 / 2017 McDonald criteria for typical clinically isolated syndrome and return whether mcdonald_ms holds from caller-assigned typical CIS, no better explanation, attacks, lesions, DIS, MRI DIT, and CSF-specific oligoclonal bands. ## Payment Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. - GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall). - HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote. - Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering. - Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional. - Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402. - offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront. - offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization. - not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search. Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers). Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments Stdio MCP (one process per host): https://magentlab.com/docs/mcp ## Guarantees - HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON. - exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE. - HTTP 402 is unpaid only. Do not sign a second authorization because of a 503. - Execution is timeout-bounded and concurrency-capped. - Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.